title: Circadian transcriptome analysis in human fibroblasts from Hunter syndrome and impact of iduronate-2-sulfatase treatment.
abstract: BACKGROUND
  Hunter syndrome (HS) is a lysosomal storage disease caused by iduronate-2-sulfatase (IDS) deficiency and loss of ability to break down and recycle the glycosaminoglycans, heparan and dermatan sulfate, leading to impairment of cellular processes and cell death. Cell activities and functioning of intracellular organelles are controlled by the clock genes (CGs), driving the rhythmic expression of clock controlled genes (CCGs). We aimed to evaluate the expression of CGs and downstream CCGs in HS, before and after enzyme replacement treatment with IDS.
  
  
  METHODS
  The expression levels of CGs and CCGs were evaluated by a whole transcriptome analysis through Next Generation Sequencing in normal primary human fibroblasts and fibroblasts of patients affected by HS before and 24 h/144 h after IDS treatment. The time related expression of CGs after synchronization by serum shock was also evaluated by qRT-PCR before and after 24 hours of IDS treatment.
  
  
  RESULTS
  In HS fibroblasts we found altered expression of several CGs and CCGs, with dynamic changes 24 h and 144 h after IDS treatment. A semantic hypergraph-based analysis highlighted five gene clusters significantly associated to important biological processes or pathways, and five genes, AHR, HIF1A, CRY1, ITGA5 and EIF2B3, proven to be central players in these pathways. After synchronization by serum shock and 24 h treatment with IDS the expression of ARNTL2 at 10 h (p = 0.036), PER1 at 4 h (p = 0.019), PER2 at 10 h (p = 0.041) and 16 h (p = 0.043) changed in HS fibroblasts.
  
  
  CONCLUSIONS
  CG and CCG expression is altered in HS fibroblasts and IDS treatment determines dynamic modifications, suggesting a direct involvement of the CG machinery in the physiopathology of cellular derangements that characterize HS.
authors.affiliation: Department of Medical Sciences, Division of Internal Medicine and Chronobiology Unit, IRCCS Scientific Institute and Regional General Hospital "Casa Sollievo della Sofferenza", S,Giovanni Rotondo (FG), Italy. g.mazzoccoli@operapadrepio.it.
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Mazzoccoli
authors.forename: Rosella
authors.initials: R
authors.lastname: Tomanin
authors.forename: Tommaso
authors.initials: T
authors.lastname: Mazza
authors.forename: Francesca
authors.initials: F
authors.lastname: D'Avanzo
authors.forename: Marika
authors.initials: M
authors.lastname: Salvalaio
authors.forename: Laura
authors.initials: L
authors.lastname: Rigon
authors.forename: Alessandra
authors.initials: A
authors.lastname: Zanetti
authors.forename: Valerio
authors.initials: V
authors.lastname: Pazienza
authors.forename: Massimo
authors.initials: M
authors.lastname: Francavilla
authors.forename: Francesco
authors.initials: F
authors.lastname: Giuliani
authors.forename: Manlio
authors.initials: M
authors.lastname: Vinciguerra
authors.forename: Maurizio
authors.initials: M
authors.lastname: Scarpa
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002940:Circadian Rhythm / Q000187:drug effects* / Q000235:genetics*; D003196:Computer Graphics; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism*; D020869:Gene Expression Profiling; D006801:Humans; D007066:Iduronate Sulfatase / Q000494:pharmacology*; D016532:Mucopolysaccharidosis II / Q000235:genetics / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D007066:Iduronate Sulfatase